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Max The Magnificent
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re: Three puzzles to ponder
Max The Magnificent   1/13/2011 2:50:17 PM
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Hi there -- when I said "the first one" I meant the first one posed by KarlS -- in the case of my three, the first one is easy -- as you say the answer is independent of the size of the planet (my specifying the diameter was a "red-herring") -- but you'd be amazed how many folks have difficulty with this one until you explain it (which I don;t want to do here so as to not give the game away)

richardst
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re: Three puzzles to ponder
richardst   1/13/2011 2:14:03 PM
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Re: Puzzle 2. As an engineering approximation, assume that the tank has a hexagonal cross-section. Hence, mark 1/6 full 1/4 way up the stick, 1/3 at 3/8, 1/2 at 1/2, 2/3 at 3/8, and 5/6 full at 3/4. That should do for a start. Otherwise, invert the formula for a circlar sector. I like KarlS's first puzzle. Solve t - 1 = t!

Radionut
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re: Three puzzles to ponder
Radionut   1/13/2011 8:26:52 AM
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Hello Max, as David states, problem no. 1 is easy: the answer is independent of the size of the planet be it 20km or 20cm or 20 million miles.

Max The Magnificent
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re: Three puzzles to ponder
Max The Magnificent   1/12/2011 2:59:19 PM
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Dang, I thought the first one would be easy .. maybe it is but as soon as i start noodling on it some crisis comes up and I get dragged away...

KarlS
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re: Three puzzles to ponder
KarlS   1/11/2011 8:30:37 PM
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If one car starts out at 30 mph and a second starts out an hour later at 60 mph, how long before the second car has gone twice as far as the first? (ignore acceleration time). At what times are the hands on a clock pointing in exactly opposite directions?

David Ashton
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re: Three puzzles to ponder
David Ashton   1/11/2011 8:01:32 AM
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Right on Glen, I spent far too much of my work day sorting those out......

zeeglen
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re: Three puzzles to ponder
zeeglen   1/11/2011 2:30:16 AM
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Assuming a balance beam scale (with counterweights) for puzzle #3 makes the math very easy. Exactly 100 Kg. A strain gauge scale takes some brain sweat with centripetal force calculations. 99.67 Kg ? #2 14.9 cm and 35.1 cm ? Circle segment area geometry, not calculus. Chords and arcs and all that neat stuff long since forgotten. Thank goodness for Wikipedia. Now my head hurts... These are interesting puzzles. Looking forward to more.

David Ashton
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re: Three puzzles to ponder
David Ashton   1/10/2011 10:13:00 PM
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Hi Max. Ref problem no. 1. The answer is easy, I won't give it away though, but the main problem that occurs to me is, how are you going to drive the wooden sticks into your stainless steel planet? I think No. 2 requires calculus, which I tried to relearn recently, this would be a good test of my knowledge...

Max The Magnificent
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re: Three puzzles to ponder
Max The Magnificent   1/10/2011 8:42:25 PM
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If you've got any good puzzles of this ilk, please email them to me at max@CliveMaxfield.com and I'll use them in a future blog...

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